In Diablo, Strength is the main focus of the Warrior and the Barbarian, both of which are classes that specialize in melee combat efficiency. Although anyone can attempt a melee against the minions of the Burning Hells if they so choose, it is often bad on one's health if he lacks the proper equipment for the job.

In addition to Strength influencing the equipment available to the hero, it also affects the damage he/she deals in a melee attack. Unlike the later entries, however, the damage bonus is not a percentage of the weapon's damage range

Warriors, Barbarians, Sorcerers, and sometimes Bards are entirely dependent on their Strength for damage dealt through weapons, as the formulae below shows:

Warrior in any melee case scenario, Barbarian using a staff, sword or unarmed, Sorcerer, Bard without a sword- Strength x clvl /100

Barbarian with an axe or a club- Strength x clvl /75

This being said, if one wishes to specialize in melee combat efficiency, it is better to try and gather up as much Strength as possible, while taking care to keep his Life and Dexterity in shape.

In Diablo II, Strength affects the actual Damage dealt by the character in case of melee weapons. It is the percentage that will be added of the Weapon's damage as is listed in the tooltip.

Strength is also a requirement to equip heavy items like Heavy weapons and Armor.

Strength can also be increased by certain magical attributes. In these cases, items that were equipped using the extra strength will remain equipped though the item will not be used, similar to items that have reached zero Durability.

Strength returns in Diablo III, as the primary stat for the Barbarian and Crusader classes. Every point in strength increase all damage output by 1% for them. In addition, for all classes, every point in strength increases the characters armor by 1 point.

Some active and passive abilities of Barbarians and Crusaders can award permanent or temporary bonuses to Strength. They can also gain 5 Strength per Core stats points in Paragon, total amount limited only by total number of Paragon levels. In addition, one can gain Strength by placing Ruby gems in armor sockets.

Barbarian and Crusader class items can only roll Strength for core stats instead of Dexterity and Intelligence, even if an item is obtained by other classes.

Strength-based classes gain 3 Strength per level, while all other classes gain 1 point per level up.